Samsung Electronics chairman Lee Kun-hee died at the age of 78 on Sunday, the company said.
Lee, who turned the South Korean firm into a global tech giant, was left bedridden by a heart attack in 2014.
"It is with great sadness that we announce the passing of Kun-hee Lee, Chairman of Samsung Electronics," the company said in a statement.
"Chairman Lee passed away on October 25 with his family, including Vice Chairman Jay Y. Lee, by his side."
"Chairman Lee was a true visionary who transformed Samsung into the world-leading innovator and industrial powerhouse from a local business," the firm said, adding: "His legacy will be everlasting."
Samsung is by far the biggest of the family-controlled conglomerates, or chaebols, that dominate business in South Korea, the world's 12th-largest economy.
The company's overall turnover is equivalent to a fifth of the nation's gross domestic product, making it crucial to South Korea's economic health.
His son, Samsung Electronics vice chairman Lee Jae-yong, has been at the helm of the company since the 2014 heart attack.
Lee was jailed for five years in 2017 after being found guilty of bribery and other offences linked to former president Park Geun-hye, before being cleared of the most serious charges on appeal and released a year later.
That case is currently being retried.